Liquid-transmission system



March 18, 19240 1,487,399

H. C. PHILLIPS LIQUID TRANSMISS ION SYSTEM Filed June' 11 1923 3 Sheets-Sheet 1 March 18 1924a H. c. PHILLfiPS LIQUID-TRANSMISSION SYSTEM 1923 3 SheetsSheet 2 Filed June 11 Maraih 18, 1924, 1,487,399

H.C.PHHJJPS LIQUID TRANSMISSION SYSTEM Filed June 11, 1925 3 Sheets-Sheet 5 FIGS 1,487,399 PATENT OFFICE.

HARRY C. PHILLIPS, 0F GLOUCESTER, ENGLAND.

LIQUID-TRANSMISSION SYSTEM.

Application filed .Tune 11, 1923. Serial No. 644,688.

To all whom it may concern:

Be it known that I, HARR CLARENCE PHILLIPS, a subject of the King of Great Britain, residing at Gloucester, in the county of Gloucester, England, have invented certain new and useful Improvements in and Relating to Liquid-Transmission Systems, of which the following is a specification.

This invention relates to meansfor transmitting power by means of any suitable liquid for use with rotary prime movers, motors, compressors, pumps, and the like, and in such manner that the usual volumetric losses may be wholly or partially eliminated and a constant predetermined amount of power transmitted.

The invention is of" the type wherein a. rotary power unit and a rotary motor unit are connected inclosed circuit by an outflow main or mains and a return main or mains. 1

According to this invention, there is provided a reciprocating piston or pistons subject to the pressure from the outflow and return mains and a pump automatically controlled by the differential pressure set up in said mains through the medium of the piston or pistons whereby, a pressure of requisite magnitude is obtained. With a requisite balancing pressure obtained, the pump may be actuated so as to reduce or cut oil the supply of liquid to the return main or mains.

In order that the invention may be clearly understood and readily carried into effect, reference is directed to the accompanying drawings illustrating a preferred embodiment of my invention.

Fig. 1 is a longitudinal elevation in part section of a liquid transmission system constructed according to this invention.

Fig. 2 isa plan.

Fig. 3 is a vertical section of a pressure or balancing pump to an enlarged scale.

In carrying the invention into effect. the liquid transmission system consists of a primary pump 1 of the rotary type which is adapted to be driven from any source of power and is hereafter called the power unit. Owing to its lubricating properties, the liquid used would preferably be oil, but any other suitable liquid maybe used as will be understood. Connected to the power unit 1 is an outflow main 2 through which liquid is discharged by the power unit 1 to a motor 3 or other driven apparatus which for convenience is termed the motor unit. A return main 4 runs "frointhe motor unit 3 to the power unit 1 whereby liquid passing through the motor unit returns to the power unit. When the motor unit is overcoming resistance by doing work, there will be set up in the outflow main 2 a pressure relatively greater than that in the return main 4. The pressure thus set up in the outflow main 2 is transmitted there-from through a pipe or conduit 5 to a piston 6 connected to an arm 7. Pivotally connected to the latter is :1. depending link 8 jointed at its lower end to a trip lever 9 which is fulcrumed at 10 to a bracket 11 secured to the pressure or balancing pump 12. The trip lever 9 bears against the underside of a trip rod 13 and lifts the suction valve 14 off its seating, this being the position when the pressures are equal in both outflow and return mains. From the pressure or balancing pump 12, a pipe 15 runs to the return main 4. Opposite the piston 6 is a lower piston 16 which is also connected to the arm 7. A pipe or conduit 17 is connected at one end with the inlet side of the power unit and thus communicates with the return main 4. The pressure or balancing pump 12 is provided with a delivery valve 18 for deliverin a charge of liquid from the sump 19 an by a cam 20 on the shaft 21 of the power unit 1.

In practice, when the pressures are normal in both outflow and return mains, 2 and 4' respectively, the pistons 6 and 16 under the influence of the spring 100, will raise lever 9, the rod 13 preventing the seating of valve 14. The pump although it continues to work, simply draws a charge past the suction valve 14 and returns the charge back to the sump 19. But when an excessive pressure is set up in the outflow main due to a resistance such as a load, this pressure acts upon the upper piston 6 and causes it to descend, and consequently, through the medium of the arm 7. link 8 and tripping lever 9, the trip rod 13. is lowered and allows the suction valve 14 to drop on to its seating. The liquid drawn in by the pump 12 is then trapped and instead of by-passing back to the sump, it is delivered by way of the delivery valve 18 to the return main 4 and commences to pump up said main. 'hen the pressure or balancing pump 12 delivering liquid to the return main 4, a

is actuated pressure is set up in the latter of any desired magnitude. When this redetermined point has been reached, the a ditional force of spring 100, acting upwardly against piston 16, in conjunction with the pressure through the conduit 17, will overcome the pressure throu h conduit 5 acting on piston 6, thereby forcing the pistons upwardly and holding valve 14 open, so that this predetermined amount of differential pressure will not be reduced, the motor receiving and applying a correspondin amount of power. Thus a predetermined ifi'erential pressure is maintai ed and a constant redetermined amount 0 power is availa'le. from the motor unit.

The pressure or balancing pump 12 may also replace any losses of liquid in the system due to leakages. When the pressure or balancing pump 12 has set up a balancing pressure or a requisite pressure in the return main 4, a reverse action can'be effected by the liquid pressure from the return main 4 being caused to pass by way of the pipe or conduit 17 to the lower piston 16 which ,acts in an opposite .direction to the aforesaid piston 6. The piston 16 having its working stroke in an upward direction, through the arm 7, and link 8 it swings up the trip lever 9 and causes the trip rod 13 to rise and to cause the suction valve 14 to lift from its seat and socut off or partially cut ofl the supply of liquid from the pres-' sure or balancing pump 12 to the return main 4, by allowing liquid to return past the suction valve 14 to the sump 19 as aforesaid. The said power unit may have any number of discharge and return branches, whi st its output may be adjusted, if necessary, to suit whatever number of branches are required to be used, whilst maintaining the same speed of flow of the liquid used in the transmission.

It is to be understood that the pipes 5 and 17 may be connected direct from the outflow and return mains 2 and 4 respectively, or from the motor unit 3 instead of from the power unit 1.

The pistons 6 and 16 as shown are arranged one above the other and have their wor ing stroke in opposite directions, but it will be understood, however, that the pistons may be arranged side by side or in any other suitable manner.

What I do claim as my invention, and desire to secure by Letters Patent, is

1. In apparatus for transmitting power by means of a liquid medium, the combination of a rotary power unit and a rotary motor unit connected in closed circuit by an outflow main and a return main, a reciprocating piston subject to the pressure from said mains, and a pump communicating with one of said mains automatically controlled by the differential pressure set up in the mains through the medium of the piston whereby a ressure of requislte magnitude is obtained in said mains.

2. In apparatus for transmitting power by means of a liquid medium, the combination of a rotary power. unit and a rotary motor unit connected in olosed circuit by an outflow main and a return main, a reciprocating piston subject to the pressure from-the outflow main and a reciprocating piston subject to the pressure from the return main, and a pump communicating with said return main, said pistons having operative means for controlling said pump for enabling a delivery of liquid to the return mam.

3. In apparatus for transmitting power by means of a liquid medium, the combination 015a rotary power unit and a rotary motor unit connected in closed circuit by an outflow main and a return main, a pair of pistons having a working stroke in opposite directions, whereby the reciprocal movement of one corresponds to that of the other said pistons being subject to the pressure from said mains, a pump communicating with one of said mains and means connected intermediately of the pistons for controlling said pump.

4. In apparatus for transmitting power b means of a liquid medium, the combination of a rotary power unit and a rotary motor unit connected in closed circuit by an outflow main and a return main, a sump, a pump having a valve which may, function as a non-return valve to close communication with said sump, while enabling delivery of 1i uid to said return main and means where y said valve is lifted from its seat so as to cause a return of liquid to said sump and thereby out 01f the supply to the said return main.

5. In apparatus for transmitting power by means of a liquid medium, the combination of a rotary power unit and a rotary.

motor unit connected ,in closed circuit by an outflow main and a return main, a pump communicating with one of said ma1ns, a piston connected to an arm, a depending ink pivotally connected to the arm, and a trip lever jointed to the link, a trip rod against which said lever abuts, means for communicating the pressure of said mains to said piston, and a valve, in said pump actuated by said trip rod and controlling flow through. the communication between the pump and said one of the mains.

In testimony whereof I affix my signature.

HARRY o. PHILLIPS. 

